There is a constant need for fittings used to convey and contain fluids. Since there are millions of these fittings used in millions of devices, it is desirable to configure these fittings so that they are both low in cost and reliable. Exemplary of such fittings are low pressure quick-connect fittings, which have replaced threaded fittings in thousands of applications, and valves which vent devices such as pressurized air containers and provide liquid drains for containers. With respect to keeping costs of such fittings as low as possible, there are needs for designs which can been machined, molded or end formed. It is also desirable to have components which are easy and inexpensive to manufacture and which do not require substantial changes in manufacturing know-how.
In configuring relatively simple devices, it is also desirable to use components and materials which have been extensively tested and have capabilities which are understood so that the limits of reliability are readily understood. This allows a designer and manufacturer to avoid over designing components so as to minimize manufacturing costs and perhaps spend manufacturing dollars on other aspects of the device using the fitting.